Alert archive / Maryland / Flash Flood Warnings in 2012

Flash Flood Warning 44, NWS Philadelphia/Mount Holly

September 2, 2012Caroline County, Maryland

NWS Philadelphia/Mount Holly issued this flash flood warning at Sep 2, 2012, 3:57 PM EDT for Caroline County, Maryland. It was in force for 2 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Sep 2, 2012, 3:57 PM EDT (19:57 UTC)
Expired
Sep 2, 2012, 6:21 PM EDT
In force
2 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

County Caroline County, MD

The radar

The Dover AFB radar (KDOX), 35 km from the middle of the area, began a volume at 20:00 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Sep 2, 4:30 PM EDTFLASH FLOODFederalsburg, MDTIME OF START ESTIMATED... ROADS ARE FLOODED.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 8.0 hours before the alert went out and 92 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Wallops Is Stn, VA at 12:00Z on 2012-09-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 448 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Wallops Is Stn, VA at 12:00Z on 2012-09-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 12 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
448 J/kg
Mixed-layer CIN
-84 J/kg
Mixed-layer LCL
1126 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
12 m²/s²
0-3 km storm-relative helicity
41 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

893 
WGUS51 KPHI 021957
FFWPHI
MDC011-030000-
/O.NEW.KPHI.FF.W.0044.120902T1957Z-120903T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
357 PM EDT SUN SEP 2 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHERN CAROLINE COUNTY...

* UNTIL 800 PM EDT...

* AT 350 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  VERY HEAVY RAIN FROM NEARLY STATIONARY THUNDERSTORMS OVER SOUTHERN 
  CAROLINE COUNTY.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO RURAL AREAS
  OF SOUTHERN CAROLINE COUNTY AROUND FEDERALSBURG.

STORM TOTAL AMOUNTS OF 2 TO 4 INCHES ARE LIKELY. RADAR ESTIMATES 
HAVE EXCEEDED TWO INCHES IN THE AREA. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. NEVER ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR IN AN
AUTOMOBILE. TURN AROUND DON'T DROWN!

PLEASE REPORT FLOODING...HAIL OR WIND DAMAGE TO THE NATIONAL WEATHER
SERVICE BY CALLING TOLL FREE...1-877-633-6772.

FLOODING IS OCCURRING OR IS IMMINENT. MOST FLOOD RELATED DEATHS OCCUR
IN AUTOMOBILES. DO NOT ATTEMPT TO CROSS WATER COVERED BRIDGES...
DIPS...OR LOW WATER CROSSINGS. TURN AROUND...DON'T DROWN! NEVER TRY
TO CROSS A FLOWING STREAM...EVEN A SMALL ONE...ON FOOT. TO ESCAPE
RISING WATER MOVE UP TO HIGHER GROUND.

&&

LAT...LON 3868 7576 3867 7580 3870 7581 3870 7584
      3869 7590 3867 7592 3869 7597 3879 7572
      3866 7570 3864 7571

$$

TFG
2 follow-up statements
341 
WGUS71 KPHI 022101
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
501 PM EDT SUN SEP 2 2012

MDC011-030000-
/O.CON.KPHI.FF.W.0044.000000T0000Z-120903T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CAROLINE MD-
501 PM EDT SUN SEP 2 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 800 PM EDT FOR
SOUTHERN CAROLINE COUNTY...

AT 453 PM EDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED THAT
ROADWAYS WERE FLOODED IN THE FEDERALSBURG AREA. WHILE THE HEAVIEST 
RAIN IS OVER, SOME OF THE FLOODING HAS YET TO RUN OFF. PLEASE
FOLLOW THE DIRECTION OF LAW ENFORCEMENT IF DRIVING LATE THIS AFTERNOON
IN SOUTHEAST CAROLINE COUNTY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY. MOVE TO HIGHER GROUND.

PLEASE REPORT FLOODING...HAIL OR WIND DAMAGE BY CALLING YOUR LOCAL
LAW ENFORCEMENT OFFICIALS OR BY CALLING THE NATIONAL WEATHER SERVICE
TOLL FREE AT...1-877-633-6772.

&&

LAT...LON 3868 7576 3867 7580 3870 7581 3870 7584
      3869 7590 3867 7592 3869 7597 3879 7572
      3866 7570 3864 7571

$$

TFG
183 
WGUS71 KPHI 022221
FFSPHI

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
621 PM EDT SUN SEP 2 2012

MDC011-022231-
/O.CAN.KPHI.FF.W.0044.000000T0000Z-120903T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CAROLINE MD-
621 PM EDT SUN SEP 2 2012

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTHERN CAROLINE
COUNTY...

THE WATERS FROM THE EARLIER HEAVY RAINS ARE RECEDING AND FLOOD WATERS
NO LONGER POSE A THREAT TO LIFE OR PROPERTY. THEREFORE...THE FLASH
FLOOD WARNING HAS BEEN CANCELLED.

LAT...LON 3868 7576 3867 7580 3870 7581 3870 7584
      3869 7590 3867 7592 3869 7597 3879 7572
      3866 7570 3864 7571

$$

TFG

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 1, 8:07 PM EDTSevere Thunderstorm WarningPHIKent, Queen Anne's38 min
Sep 1, 8:47 PM EDTSpecial Weather StatementPHICaroline, Queen Anne's88 min
Sep 1, 9:27 PM EDTSpecial Weather StatementPHICaroline, Queen Anne's, Talbot93 min
Sep 1, 10:34 PM EDTSpecial Weather StatementPHICaroline, Talbot86 min
Sep 1, 11:44 PM EDTSpecial Weather StatementPHIWicomico61 min
Sep 2, 12:40 PM EDTAreal Flood AdvisoryPHICecil83 min
Sep 2, 3:17 PM EDTAreal Flood AdvisoryPHICaroline118 min
Sep 2, 6:33 PM EDTSpecial Weather StatementPHIKent117 min

Nearby

Flash Flood Warnings in Maryland, 2012Every flash flood warning in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.